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How To Fix a Catalytic Converter Without Replacing It

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How To Fix a Catalytic Converter Without Replacing It

A catalytic converter is an integral part of you car, and is usually designed to last your cars lifetime. But when it becomes faulty, it may be hard to cash out for such an expensive part, even though in doing so, will prevent further engine issues from arising. So some may question how to fix a catalytic converter without replacing it. Or if that’s even an option at all.

If you want the quick answer, Yes, it is possible to fix a catalytic converter without replacing it, but only if the converter hasn’t become so bad that it rattles, is discolored, warped, or has a sulfur smell. The way of fixing it is usually pretty simple, the easiest using a lacquer thinner, with other options like taking it out and washing, etc. All of this will be discussed later in the article.

What Is a Catalytic Converter?

This is a part that is not only essential but is an expensive part of your exhaust system. Its main purpose is to clean toxic emissions, it does this by converting them into carbon dioxide, nitrogen, and water vapor.

These toxic emissions are a byproduct of engine combustion, so there is no getting around producing them. But the effects of it can be reduced with a catalytic converter, as it uses metals such as platinum and pallidium to convert these toxins into safer gases before they exit your tailpipe.

The catalytic converter is what allows you to pass the emissions test. Failing to pass emissions is an indicator that you have a catalytic converter problem. This part is expensive to replace because of the precious metals it contains. It can cost well over $1,000 to replace one, so it’s better to know when it fails and how to fix it.

How Do You Know When the Converter Has Problems?

There are multiple signs when a catalytic converter has issues, but those issues may not require replacement. It could be that it is just lightly clogged or dirty. Hence It is important to know the differences in symptoms that indicate your catalytic converter will need replacement versus cleaning.

These Include:

Possibly Needs Replacement

If you experience any of those symptoms below, it may not be possible to fix the catalytic converter, and the only choice is to replace it. These include:

1. Rattling Noises

It’s important to always pay attention to sounds your car is making, as that could tell a lot about the problems your car is having. The sound of the converter rattling, is one of them.

How a good catalytic convert will look on the inside

This sound starts happening when the metals inside start breaking off from the converter’s filtering system, which looks like a honeycomb. As they crumble, they can begin to rattle.

How a bad catalytic convert will look on the inside

2. Discoloration or Warping

A change in the way your catalytic converter looks is a sure sign that it needs replacing. Discoloration or warping means it has an internal leak or is chronically overheating.

3. Sulfur Smell

While this symptom can be the result of either a failing catalytic converter or one that simply needs cleaning, a sulfur smell typically happens because it can’t convert the toxins into other less harmful substances.

This smell, which is similar to rotten eggs, will be most noticeable around the exhaust. Specifically, the catalytic converter doesn’t convert hydrogen sulfide, produced as the vehicle burns a gas, into sulfur dioxide, which causes the smell

Another symptom associated with the sulfur smell is the substance coming out of your car is much darker than normal. It could even be a cloud of black smoke.

Possibly Needs Cleaning

If your catalytic convert doesn’t rattle, have discoloration, warping or a sulfur(rotten egg) smell, then you might be able to fix it by cleaning instead of replacing it. Those signs include:

1. Your Vehicle Loses Performance

When your catalytic converter is clogged, it can’t release gases fast enough, causing the engine to “choke”. Which decreases the efficiency, and thereby affecting performance of the vehicle

2. Gas Mileage Decreases

A sure way of identifying a clogged catalytic converter is by bad gas mileages. This is because the fuel to air ratio changes when the exhaust pushes some toxins back into the engine. This also affects combustion reaction and that decreases your gas mileage as well as performance.

3. Poor acceleration or a sluggish start

Those having trouble starting or accelerating their car can look at the catalytic converter as the primary issue. Clogs may be preventing gases from leaving the exhaust and choking your engine.

4. Check Engine Light On

Some people ignore the check engine light because they feel it means big bucks at the dealer, but it is something that you should pay attention to when it happens. Usually, this is the first sign that something is wrong with the catalytic converter.

A light to check your engine doesn’t mean you need to rush to a dealer. A good investment is a scanner called an OBD2. This diagnostic tool can give you codes that line up to specific problems with your vehicle.

These devices are what mechanics use and can be purchased easily for under $50. Then you will know for sure whether it is your catalytic converter or something else.

Related: What Does The Service Engine Soon Light In My Car Mean?

Fixing Your Catalytic Converter Instead Of Replacing It

You can do several things to remedy catalytic converter issues without a lengthy repair or trying to replace it. These are all simple things that are worth trying first before shelling out big bucks for a replacement.

But as said earlier, if your catalytic converter has:

  • Rattling noises
  • Discoloration
  • Warping
  • Sulfur Smell

It may not be possible to fix it without replacing it completely. If that’s not the case, here’s how to fix your catalytic converter without replacing it:

1. Use Fuel Additives

Using a fuel additive every once in a while will boost your engine’s performance and help clean your catalytic converter. This is especially true for those who use regular gasoline rather than premium or super-premium, as those higher-cost types of gasoline have additives in them.

Those who are having some trouble with engine performance, bad gas mileage, or other catalytic issues can also try going with a premium or super-premium gas for a while to see if that improves the vehicle’s performance or resolves issues.

You can try using a lacquer thinner for that. All you have to do is put a full gallon of the thinner into a half-full gas tank. Then, take a road trip where you can drive at highway speeds for about 150 miles. Another option is to run the vehicle in the driveway at about 2500 RPMs for about a half-hour.

Doing this will rid the vehicle of all the nasty stuff that gets stuck in your catalytic converter and allow the converter to function optimally again.

2. “Wash” Your Catalytic Converter

You can try “washing” your catalytic converter, but this will require taking off the catalytic converter. This may scare someone not familiar with mechanical things, but it’s not as hard as it seems. All you have to do is to take it out and pressure wash all the junk that has accumulated inside the converter.

You will need to clean the part from both the front and back end to get it all.

To get a deep clean, soak the part with a standard laundry detergent or degreaser in hot water. Be sure to use something that specifically cuts through the heavy grease build-up. Afterward, power wash it, dry it completely and reinstall it.

3. Drive Hard

The name might sound funny, but this is a good method for resolving basic issues with your vehicle, including the catalytic converter. To understand why this works, you must first learn how the catalytic converter works.

Catalytic converters need to be pushed hard at times to reach an efficient temperature to operate. That is between 800 Fahrenheit and 1,832 degrees. The issue is that most people never drive a vehicle hard. They typically drive short trips at slower speeds to work, or pick up the kids.

That type of easy driving can cause your catalytic converter to fail early because it never reaches the optimal temperature to do its job.

Drive hard, pushing the vehicle to “its limits” for several miles. Take the vehicle to the open road, and accelerate quickly. Run it at a higher speed, then take your foot off the gas before hitting it again. Do this several times.

This heats your converter and burns off deposits lodged in the converter, but also the intake, sensors for oxygen, the cylinder heads, and throughout the exhaust. But above all, make sure you do it safely.

Treat The Cause

It’s never a good idea to treat the symptom, instead of the cause. Typically, catalytic converters are designed to last a vehicle’s lifespan (about 100,000 miles) and failure is uncommon. Meaning that failure of a converter is likely related to larger issues rather than a catalytic converter itself. There are generally two causes for a catalytic converter to fail:

  • Fouled or plugged as a result of too much oil: Engine oil seepage in the exhaust system can clog up the air passages by producing heavy soot and so coating the catalyst, leading the converter to fail in decreasing harmful emissions while also boosting backpressure, causing heat and exhaust to back up into the engine compartment.
  • Excessive Heat: The ECM could be receiving faulty air/fuel mixture signals due to a bad oxygen sensor, blocked injectors, or a dirty MAF sensor. This causes the engine to run too lean or, in some situations, too rich. This makes the car to generate more heat than it was designed to handle, and will cause the converter to glow cherry red, which will destroy it very quickly. But In most circumstances, you will receive signals that something is wrong before anything goes really bad, in a form of a check engine light

Should I Fix Or Replace My Catalytic Converter?

Replacing a catalytic converter is not cheap, and is mostly done on really old cars anyway. For most vehicles, the cost of repairing a catalytic converter ranges between $945 and $2475, including the piece itself and labor, but can go as high as $2250. Which could cost just as much as your car, or even more if you have an older car. 

So if you planing to sell your car, or just leaving it in the junk yard, fixing the catalytic converter would probably be the better option money wise. But if your car is worth much more then the catalytic converter, it would be a good idea to replace it, as you would have a hard time selling a “newer” car which can’t pass the emissions test and has multiple engine problems because of it.

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